You had to feel sorry for Mo'Nique, as she tiptoed onstage at the Academy of Motion Picture Arts and Sciences in Los Angeles last Tuesday to unveil the list of nominees for the year's Oscars – and not just because the job required her to appear under bright lights, in full cocktail attire, at the ungodly hour of 5.30am.

Her booking was supposed to recall the red-letter nature of the 2010 awards, when Kathryn Bigelow became the first female Best Director, and a film called Precious made it a night to remember for black cinema, helping its African-American talent win a record three gongs, including one for Mo'Nique as Best Supporting Actress, from a record eight nominations.

This year, the mood couldn't be more different. Confounding the hopes of everyone who dared think that the statuettes raised by Mo'Nique and her colleagues last March might herald a bright future for minority cinema, 2011's Oscars have turned into the whitest in recent history. Not a single black man or woman has been shortlisted for any major award. Neither is black talent represented in any of the myriad technical categories. The 10 films shortlisted for Best Picture are, as a BBC honcho once put it, "hideously" white.

Things are so bad, on this front, that it seems that Vanity Fair invited Anthony Mackie (a fine actor, but not a player in this awards season) to create a semblance of diversity by taking part in the cover shoot of its new Hollywood edition. The Hurt Locker star is shoehorned uneasily alongside a dozen young, white colleagues, all of whom are connected to Oscar contenders.

Meanwhile, at last week's Producers Guild Awards, the Asian comedian Aziz Ansari ventured near the knuckle, wondering why David Fincher didn't get at least one black kid to check his Facebook account in The Social Network, and joking that 127 Hours is so monochrome that even James Franco's arm fails to turn black when he uses a pen-knife to cut it off.

His rumblings prompted unease among Hollywood's bleeding heart liberals. And for good reason. Though the Academy tends to be ahead of the curve in honouring minorities (when it gets the chance), the same can't be said of the wider film industry.

The reason no black films are in the Oscar picture is quite simple: no award-worthy ones were released in 2010. Tyler Perry's For Coloured Girls gained little traction with critics. Takers, a slick action movie, lacked depth. Night Catches Us, a decent film by Tanya Hamilton, was given only a limited release by Sony Classics. Two other black titles – a comedy, Lottery Ticket, and a summer romance, Just Wright – were fly-weight.

The absence of black film matters, for it lays bare a wider problem: by failing to represent the roughly 15 per cent of Americans who have black skin, the film industry lays bare its increasing reluctance to embrace anything from even slightly outside the mainstream.

Driving this problem is finance: as movie budgets have risen, producers have become reluctant to take risks. The mindset prevents studios from taking a punt on films that are not guaranteed to appeal to a broad demographic. This further homogenises the already dumbed-down fare in cinemas. So, next time you berate the rubbish screened at multiplexes, bear in mind that it stems from a dearth of variety. And one reason for that dearth is the decline of films about people of colour.

Audiences understand this. It was, perhaps, no coincidence that two of the biggest studio flops of last summer were The Last Airbender and Prince of Persia: The Sands of Time. In both films, the makers excluded minority talent: Prince of Persia's lead was played not by an Iranian, or even a Middle Eastern actor, but by an unshaven Jake Gyllenhaal. In The Last Airbender, a white child actor was cast in the supposedly Asian lead role.

Studios do not get it, though. Few people of colour exist at the higher or middle echelons of the industry. Not a single studio head has ever been black. Visit a sound stage and you'll do well to spot a black stagehand, cameraman or film producer, let alone executive.

Rocky Seker, who worked with a director at Sony in the 1990s, quit the studio after becoming disillusioned with racial politics there. She is now the curator of Black Cinema at Large, the Northern California affiliate of the African-American Film Festival Releasing Movement, which attempts to give prominence to black films.

"When I was working at Sony, there was some great black talent and it just wasn't being listened to. None of the projects were being green lit," she says. "It was very palpable. You felt that people didn't really want to have you there and were only half listening to what you had to say."

Seker adds that the black Oscar glories of recent years have tended to play to stereotypes. Denzel Washington, Best Actor for Training Day in 2002, was an angry young man. Halle Berry, who the same year won for Monster's Ball, exposed herself sexually. Precious ventured into cliché: in one scene, its star runs down a New York street carrying stolen fried chicken.

Her take is shared by Jeff Friday, CEO of Film Life, a distributor specialising in black-themed films. He points to a plethora of directors, including Spike Lee, Malcolm Lee, John Singleton, F Gary Gray and Forest Whitaker, who find it tougher than they should to get studio projects off the ground. "These are guys at the top of their profession, some of the best there is, and you see them directing a film, what, every three to four years? Then you look at white directors of a similar age and status, and they are each doing two or three films every year," he says. "Black directors cannot get films made and are not being hired to make big films when they should be. It's incredibly frustrating."

To Friday, ignoring black film also makes bad commercial sense for studios. "A whole market is not being addressed," he says. "African-American box office used to be the fastest-growing sector in the nation. Well, in the last three years it's been down. Black people are not going to movies at the rate they used to, because they are not being catered for."

It wasn't ever thus. Black cinema's roots go back to the birth of film as a commercial art form: profitable silent movies were being made for the black community of Chicago in 1910. After the "talkies" arrived, the industry struck a partial blow for equality when Hattie McDaniel won 1939's Oscar for Best Supporting Actress in Gone with the Wind (though she had to sit in the segregated section of the theatre on the night). Of perhaps greater significance, given that it occurred during the civil rights struggle, was the decision to award Sidney Poitier an Oscar in 1963, when he was named Best Actor as the lead in Lilies of the Field. He, more than any star, showed that black actors could carry mainstream hits.

A decade later saw the rise of so-called "Blaxploitation" films, focusing on black urban culture. Melvin Van Peebles kickstarted the movement in 1971 with Sweet Sweetback's Baadasssss Song. The best-known title is Shaft. Aside from Westerns, the Blaxploitation films are still considered America's only indigenous genre of movie.

Black film's glory years , however, were the two decades that began with the success of Spike Lee's She's Gotta Have It in 1986. Soon after came Robert Townsend's Hollywood Shuffle and John Singleton's Boyz * the Hood. At one point, at least a dozen studio titles a year could be billed African-American movies. Many of these films were biopics paying homage to prominent black figures: Ike and Tina Turner in What's Love Got to Do with It, Malcolm X, Muhammad Ali in Ali, the boxer Rubin Carter in The Hurricane. The last Oscar success for such films was in 2004, when Jamie Foxx won a gong for the Ray Charles biopic Ray.

If we're being charitable to the industry, the decline in black film has perhaps been part of a decline in independent film. Five years ago, studios began closing their speciality divisions, in part as a response to falling DVD sales, which had traditionally helped smaller movies turn a profit. As these units went, so did the business model for smaller, quirkier film projects.

There is but one spot of sunlight on the horizon: the growing potential for film to be streamed online could create a business model where films can find paying viewers without having to secure expensive distribution deals. Titles with smaller target demographics could start to make financial sense. "In the next few years, as film-makers start to embrace web distribution, you will get more potential to recoup the investment for smaller films, which could be conducive to minority representation," says S T VanAirsdale, editor of the website Movieline. "We've just actually had a surprisingly good Sundance for film sales, and don't forget that Oprah Winfrey now runs an entire network. She was there, and bought the documentary Becoming Chaz."

Oprah executive-produced Precious and was central to its success. Could she eventually save black film? It's a big ask, but aside from the internet, she is probably the nearest thing the industry has to a great white hope.